Trouble downloading pdf files created on webserver

Just today some of my customers are complaining that the PFD (that is created by ASPPDF) cannot be downloaded/open.  Now some with in the company can and some cannot.  Even with those that cannot it does create it on the server and starts the download process.  When they try to "open" and or "save as" it locks up.  This is happening to multiple companies and therefore why I think you can help.  Was there any updates this morning that may effect the download/open process?  With PDF or Windows, etc...